Honeywell User Group: Understand risk
No industrial control system can ever be 100% secure, that is a given, but a manufacturer has to understand the threat and know how far they want to go and still remain confident they can withstand the inevitable attack.
“Cyber security is all about risk,” said Sinclair Koelemij, technical team lead Open Systems Services EMEA at Honeywell Process Solutions during his talk on designing a secure industrial control system at the 2013 Honeywell User Group (HUG) EMEA in Nice, France. “You have to decide at what level you want to be.”
“Defense for critical infrastructure needs to be more protected than it was 10 years ago,” Koelemij said. “We have seen some drastic changes; for the first time malicious code was used to attack an (industrial control system).” While attacks of late have not caused heavy damage, they have been more stealthy in trying to steal intellectual property, Koelemij added one of the bigger hits came last August when a virus called Shamoon hit Saudi Aramco and wiped out at least 30,000 hard drives. “Shamoon just wanted to attack and do as much damage as possible.”
He added another type of attack has also inflicted damage and that is a ransomware attack. That is when a virus gets on a computer and locks the system and demands a payment to unlock the computer. If a victim does pay, oftentimes, the bad guy does not “fix” the system.
In short, Koelemij said malware can:
- Reduce system performance
- Create a loss of view or information
- Be a production disruption
- End up being costly to remove an infected system
- Lead to a loss of intellectual property.
That is why manufacturers have to understand what they are trying to protect and know what the risk is before they start or refresh a security program.
Security, Koelemij said, can end up measured on impact to safety, people, finance and brand name. Part of that is identifying risk, and then protect, detect, respond and then have a plan to recover.
“You have to decide on your risk appetite,” he said. In the protect mode, the user needs to determine what technologies they want to employ, like firewalls, antivirus, or whitelisting to name a few.
They then have to come up with a response plant. “You need to take action. If you are sitting with your arms crossed until the attack is over, then you are too late,” he said. “If you don’t respond very quickly the damage will end up much bigger.”
“The golden rule in security is if the time to breach the protection is greater than the time to detect the event plus the time to respond to the event, then your plant is secure.”
To achieve that golden rule, users need to work in technical controls like antivirus, firewalls, application whitelisting, intrusion prevention systems, domain controllers, intrusion detection systems. Those technical controls will help achieve safety assurance levels.
There are also non technical controls like policies, procedures, security incident response, and risk management, which are more the maturity levels.
Knowing what type of attacker could hit you can determine your security level. The ISA99/IEC 62443 security standard defines security levels.
- Security level 1 (SL1) is something that happens by chance, a very low level type of attack
- Security level 2 (SL2) is protection against intentional security incidents.
- Security level 3 (SL3) is protection against a targeted attack like the Shamoon virus.
- Security level 4 (SL4) protects against intentional security incidents using sophisticated means. This would be more of a nation-state attack like Stuxnet, which struck and damaged a nuclear enrichment facility in Natanz, Iran.
Generally, non critical manufacturing operates at security level 2, while critical infrastructure is usually between levels 3 and 4, Koelemij said. Oil and gas, power, and water facilities are usually at security level 3, he said.
But it isn’t all about the technical side as you also have to look at what processes are in place to help ward off attackers.
That is when you look at which maturity level the manufacturer is at. That range goes from maturity level 1 up to maturity level 4. Maturity level 1 is where the user is practicing security, but has no real plan formulated, where ML4 has a solid plan in place where there are plenty of policies and procedures in place.
“So, far I have not seen a maturity level 4 in real life,” Koelemij said. “In our security assessments, most companies score between SL1 and SL2. I have seen companies that are really protected, but they are rare.”